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arXiv · 2608.19864

Volatile resistive-switched state in a bulk organic conductor with a sharp metal-insulator transition

Riku Ishii·Ryo Motohashi·Keitaro Tada·Yusuke Suzuki·Takayoshi Kouchi·Hiroshi Oike·Fumitaka Kagawa·Reizo Kato·Tetsuaki Itou
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Abstract

Volatile resistive switching in correlated-electron systems, characterized by an abrupt resistance decrease under applied current, is crucial for developing next-generation electronics. Despite its technological significance, the underlying physics remains elusive. Inorganic thin films on substrates---the widely studied platform for resistive switching---usually exhibit broad temperature-induced metal-insulator transitions (MITs) and substantial heat dissipation. These factors complicate the nonlinear thermal effect induced by Joule heating, a key contributor to resistive switching, rendering it excessively complex and difficult to decipher. Here we investigate a resistive-switched state in the bulk organic conductor ($d$7-DMe-DCNQI)$_{2}$Cu, which undergoes an extremely sharp first-order MIT and exhibits weak heat dissipation, using resistance and $^{1}$H-NMR measurements. These extreme conditions make the Joule heating effect vivid, allowing us to observe peculiar phenomena, including temperature locking to the MIT and `inverse Ohm's law'---an inverse proportionality between voltage and current. These findings provide fundamental insights into the nonlinear thermal effect in resistive switching, offering a pathway to efficient resistive-switching technologies.

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Riku Ishii, Ryo Motohashi, Keitaro Tada, Yusuke Suzuki, Takayoshi Kouchi, Hiroshi Oike, Fumitaka Kagawa, Reizo Kato, Tetsuaki Itou. 2026-08-20. Volatile resistive-switched state in a bulk organic conductor with a sharp metal-insulator transition. https://doi.org/10.1103/3yjz-8f9d

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